"Obviously the timing for this isn't ideal, but Billie Joe’s well-being is our main concern,” the band's bassist, Mike Dirnt, said in a news release. “We are happy to say that Billie Joe is doing well, and we want to thank you all for the outpouring of support and well wishes that we have received, and we can’t wait to see you all again soon."

The new Portland date will be announced shortly, and previously purchased tickets will be honored. In total, the band postponed 21 shows stretching into February.

The band also announced it would cancel its nine remaining 2012 appearances, giving fans refunds. Fans so have something to look forward to, however, while they wait for Armstrong's return. Green Day announced they would move up the release date of Green Day Tre to Dec. 11, 2012 from Jan. 15, 2013.